Title:
	Inter- and Intra-Processor Synchronizations
	in Multiprocessor Real-Time Kernel

Authors:
	Hiroaki Takada and Ken Sakamura

	Department of Information Science,
	Faculty of Science, University of Tokyo

Abstract:
	In multiprocessor systems, the worst-case execution time of
	a task that exclusively accesses a shared resource is
	unavoidably prolonged as the number of contending processors
	is increased.  In case of function-distributed
	multiprocessors, because many of the tasks can be processed
	without synchronizing or communicating with other
	processors, it is advantageous that the worst-case behavior
	of such tasks are determined independently of the activities
	of other processors and of the number of processors in the
	system.  In this paper, we propose two methods to realize
	multiprocessor real-time kernels satisfying this property.
	The first method is an implementation technique in which the
	precedence in acquiring an inter-processor lock is given to
	the host processor of the lock.  The second method is to
	classify tasks into local tasks and private tasks.  Private
	tasks have improved scalability and responsiveness, though
	they cannot synchronize or communicate with other
	processors.  The effectiveness of our proposals is
	demonstrated through performance evaluations.

Appeared in:
	Proceedings of 4th International Workshop on Parallel
	and Distributed Real-Time Systems (WPDRTS)